Re: [PATCH v3 4/7] migration/block-dirty-bitmap: fix bitmaps pre-blockdev migration during mirror job

[Eric Blake]

On 5/19/20 5:51 AM, Vladimir Sementsov-Ogievskiy wrote:
> 18.05.2020 23:36, Eric Blake wrote:
> > On 5/15/20 7:40 AM, Vladimir Sementsov-Ogievskiy wrote:
> > > Important thing for bitmap migration is to select destination block
> > > node to obtain the migrated bitmap.

> > > +        /* Skip filters without bitmaos */
> > > +        while (bs && bs->drv && bs->drv->is_filter &&
> > > +               !bdrv_has_named_bitmaps(bs))
> > > +        {
> > > +            bs = bs->backing->bs ?: bs->file->bs;
> >
> > Is this correct, or should it be:
> >
> > bs = bs->backing ? bs->backing->bs : bs->file->bs;
>
> Hmm, yes, otherwise it should crash on file-based filter :)
>
> > Otherwise looks reasonable, but I'm hesitant to include it in today's 
> > bitmap pull request in order to give it more review/testing time.  It 
> > should be ready for a pull request next week, though.

Can you post a v4, to make it easier for me to build?

--
Eric Blake, Principal Software Engineer
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